Building native compiler for Android-x86 6.0.1

[Jihyun Son]

I have been trying to compile some sources such as powertop to analyze my tablet's power consumption.

Simply too hard to get it done by putting those codes into external/powertop tree with dependancies.

(Well I don't like all the ways I should use Android.mk...)

So I thought very thumb way: can I build native gcc compiler for Android-x86?

Spent a whole day... Got it working but I don't know that's enough.

- download android ndk and make standalone toolchain for API 23, because I'm on MM 6.0.1

- using the toolchain with included sysroot, build binutils-2.25.1 and gcc-4.9.3 with mpc, mpfr, gmp.

- put all together into some place in my tablet. (/system/gcc in my case)

- make hello world code and compile with PIE support.

- success.

So I'm going to build powertop, hope it will go well without any issue.

P.S: Should I care about bionic? I heard that's a standard C library but what's different than sysroot from NDK toolchain?

[Chih-Wei Huang]

2016-03-20 19:28 GMT+08:00 Jihyun Son <itaz...@gmail.com>:
> I have been trying to compile some sources such as powertop to analyze my
> tablet's power consumption.
> Simply too hard to get it done by putting those codes into external/powertop
> tree with dependancies.
> (Well I don't like all the ways I should use Android.mk...)

You should just learn how to write an Android.mk.
Or you have to go through all the details of "cross-compile".

> So I thought very thumb way: can I build native gcc compiler for
> Android-x86?
>
> Spent a whole day... Got it working but I don't know that's enough.
>
> - download android ndk and make standalone toolchain for API 23, because I'm
> on MM 6.0.1
> - using the toolchain with included sysroot, build binutils-2.25.1 and
> gcc-4.9.3 with mpc, mpfr, gmp.
> - put all together into some place in my tablet. (/system/gcc in my case)
> - make hello world code and compile with PIE support.
> - success.

This didn't give you any benefit to your problem.
What you got is just the same binaries in AOSP's prebuilts/gcc/.

The reasons to build toolchains manually are

* You want to learn the techniques to build toolchains
* You want to fix some issues in the prebuilt toolchains

Your problem doesn't fall into these categories I think.

> So I'm going to build powertop, hope it will go well without any issue.

Nope.

> P.S: Should I care about bionic? I heard that's a standard C library but
> what's different than sysroot from NDK toolchain?

Sure. The bionic is Android's C library and
your executable must link with it.

Anyway, I suggest you do more research first
before trying to do something.
I'm very sure someone has ported powertop to Android.
You just need to google it.


--
Chih-Wei
Android-x86 project
http://www.android-x86.org

[Jihyun Son]

Yeah, you got me.
Nothing left to try more with this bare compiler inside Android-x86.
Just I got some lessons like how to DO cross compile.
I like just try and do before think, huh, sometimes good, sometimes bad. This time? So-so..

I'm googling powertop for Android and somebody already posted that as you said.
Gonna try it and better learn how to use Android.mk

Thanks for the reply.